Business Combination - Unaudited Pro Forma (Details) - Comerica Incorporated - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Business Combination [Line Items] | ||||
| Unaudited pro forma net income available to common shareholders | $ 904 | $ 773 | $ 1,668 | $ 677 |
| Income Statement Location [Axis]: us-gaap:InterestIncomeExpenseNet | ||||
| Business Combination [Line Items] | ||||
| Unaudited pro forma revenue | 2,201 | 2,118 | 4,338 | 4,174 |
| Income Statement Location [Axis]: us-gaap:NoninterestIncome | ||||
| Business Combination [Line Items] | ||||
| Unaudited pro forma revenue | $ 1,059 | $ 1,037 | $ 2,066 | $ 1,974 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of pro forma revenue of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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